Map information processing apparatus

ABSTRACT

An apparatus includes a map information storage section ( 16 ) that stores map information on an area by area basis formed in meshes; a positioning section ( 15 ) for measuring its own present location; a new road detecting section ( 19 ) for deciding that a new road is detected when the present location is determined to be on a road not included in the map information; a new road registration decision section ( 20 ) for deciding that the new road is registerable to the map information stored in the map information storage section when the road density in the area including the new road is equal to or less than a predetermined value; and a new road registration section ( 21 ) for registering the new road to the map information stored in the map information storage section, when the new road is determined to be registerable.

TECHNICAL FIELD

The present invention relates to a map information processing apparatusfor processing map information to be displayed, and more particularly totechnology for automatically updating existing map information when anew road is detected.

BACKGROUND ART

Conventionally, a map information processing apparatus has been knownwhich updates, when traveling a place whose roads are not recorded inits own map information, its map information by detecting the travelingroute from its traveling record and by adding it to the map informationas a new road. If such a map information processing apparatus adds a newroad having a positioning error to the existing map information, a userwill suffer a great disadvantage because a result of a subsequent routesearch will differ from an actually travelable route.

Accordingly, Patent Document 1, for example, discloses a car navigationsystem that makes a decision as to whether a new road is to be added tothe existing map information or not using receiving conditions of a GPS(Global Positioning System). If the present location detected by aposition detecting means is not present on any road indicated by the mapinformation stored in the initial recording area of a navigationrecording medium, the car navigation system carries out the processingrepeatedly that acquires the present location and writes it to anadditional recording area of the recording medium. During theprocessing, the car navigation system estimates the GPS receivingconditions, that is, the positioning error contained in the new roadinformation, from the number of GPS satellites from which the GPSsignals can be received. Then, it adds the new road information to theexisting map information only when the estimated error is smaller than aprescribed value. The configuration can prevent generating and recordingnew road information from the GPS signals in poor receiving conditions,and thus prevent the new road information having the positioning errorfrom being added to the existing map information.

Patent Document 1: Japanese patent application laid-open No. 2002-48559.

The technique described in the foregoing Patent Document 1, however, hasthe following problem. Specifically, the positioning error can actuallyexist in spite of good GPS receiving conditions, and particularly urbanareas have a problem of the so-called multipath problem caused by thatsurrounding buildings reflect the signals from the GPS satellites.Accordingly, even if the number of GPS signals received from the GPSsatellites is enough, the positioning error can sometimes be very large.Thus, the technique, which estimates the positioning error of the newroad from the GPS receiving conditions and employs the estimation resultas a reference for deciding whether to register the new road as anadditional record, presents a problem of exerting adverse effect on theexisting functions such as the navigation functions.

The present invention is implemented to solve the foregoing problem.Therefore it is an object of the present invention to provide a mapinformation processing apparatus capable of circumventing the adverseeffect on the existing functions by registering only after anappropriate decision as to whether to make additional registration ofthe new road to the existing map information.

DISCLOSURE OF THE INVENTION

A map information processing apparatus in accordance with the presentinvention includes: a map information storage section for storing mapinformation on an area by area basis formed in meshes; a positioningsection for measuring its own present location; a new road detectingsection for deciding that a new road is detected when the presentlocation measured by the positioning section is on a road not includedin the map information stored in the map information storage section; anew road registration decision section for deciding that the new road isadditionally registrable to the map information stored in the mapinformation storage section when road density in an area including thenew road detected by the new road detecting section is equal to or lessthan a predetermined value; and a new road registration section formaking additional registration of the new road, as to which the new roadregistration decision section makes an additionally registrabledecision, to the map information stored in the map information storagesection.

According to the present invention, the map information processingapparatus is configured in such a manner as to decide whether to makeadditional registration of the new road to the existing map informationbased on the road density in an area formed by dividing into meshes.Thus, it can add the new road not written on the map to the existing mapinformation with preventing the adverse effect on the existing functionsdue to the addition of the new road, which can include a positioningerror, to the existing map information.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a configuration of a map informationprocessing apparatus of an embodiment 1 in accordance with the presentinvention;

FIG. 2 is a flowchart illustrating registration decision processingcarried out by a new road registration decision section of the mapinformation processing apparatus of the embodiment 1 in accordance withthe present invention;

FIG. 3 is a flowchart illustrating the registration decision processingcarried out by the new road registration decision section of the mapinformation processing apparatus of an embodiment 2 in accordance withthe present invention;

FIG. 4 is a flowchart illustrating the registration decision processingcarried out by the new road registration decision section of the mapinformation processing apparatus of an embodiment 3 in accordance withthe present invention;

FIG. 5 is a block diagram showing a configuration of the map informationprocessing apparatus of an embodiment 4 in accordance with the presentinvention;

FIG. 6 is a flowchart illustrating registration processing carried outby a new road registration section of the map information processingapparatus of the embodiment 4 in accordance with the present invention;

FIG. 7 is a flowchart illustrating the details of the registrationdecision processing shown in FIG. 6;

FIG. 8 is a diagram illustrating route calculating processing carriedout by a route calculating section of the map information processingapparatus of the embodiment 4 in accordance with the present invention;

FIG. 9 is a diagram illustrating a starting point and ending point setin the route calculating processing carried out by the route calculatingsection of the map information processing apparatus of the embodiment 4in accordance with the present invention;

FIG. 10 is a flowchart illustrating the registration decision processingcarried out by the new road registration decision section of the mapinformation processing apparatus of an embodiment 5 in accordance withthe present invention;

FIG. 11 is a flowchart illustrating the details of the road typedecision processing of the new road illustrated in FIG. 10;

FIG. 12 is a block diagram showing a configuration of the mapinformation processing apparatus of an embodiment 6 in accordance withthe present invention;

FIG. 13 is a flowchart illustrating the registration decision processingcarried out by the new road registration decision section of the mapinformation processing apparatus of the embodiment 6 in accordance withthe present invention;

FIG. 14 is a flowchart illustrating the registration decision processingcarried out by the new road registration decision section of the mapinformation processing apparatus of an embodiment 7 in accordance withthe present invention;

FIG. 15 is a block diagram showing a configuration of the mapinformation processing apparatus of an embodiment 8 in accordance withthe present invention;

FIG. 16 is a flowchart illustrating processing carried out by aregistration decision result presentation section and a registrationdecision result confirmation section of the map information processingapparatus of the embodiment 8 in accordance with the present invention;and

FIG. 17 is a diagram illustrating the operation of the map informationprocessing apparatus of the embodiment 8 in accordance with the presentinvention.

BEST MODE FOR CARRYING OUT THE INVENTION

The best mode for carrying out the invention will now be described withreference to the accompanying drawings to explain the present inventionin more detail.

Embodiment 1

FIG. 1 is a block diagram showing a configuration of a map informationprocessing apparatus of an embodiment 1 in accordance with the presentinvention. The map information processing apparatus comprises a carnavigation system 1, a display unit 2, a speech output unit 3, an inputunit 4, a vehicle speed sensor 5, a GPS receiver 6 and an accelerationsensor 7. The car navigation system 1 has a function of updating the mapinformation in addition to the well-known navigation functions. The carnavigation system 1 will be described in more detail later.

The display unit 2 is composed of a liquid crystal display unit, forexample, and displays a map image for display and the optimum route to adestination in accordance with display data delivered from the carnavigation system 1. The speech output unit 3 is composed of a speaker,for example. It outputs speech for guiding the user to the destinationalong the optimum route, and speech about prescribed informationincluded in the map information in accordance with the speech datadelivered from the car navigation system 1.

The input unit 4 is composed of input buttons mounted on the main panelconstituting the front of the car navigation system 1, a remote controlfor sending an input signal equivalent to that of the input buttons, atouch panel placed on the screen of the display unit 2 or a microphonefor making a speech input (none of them is shown); or is composed of acombination of them. The input unit 4 is used by the user to input a maparea to be displayed on the display unit 2, and the starting point,ending point and the like for calculating the optimum route. The inputsignal fed from the input unit 4 is delivered to the car navigationsystem 1 as operation data.

The vehicle speed sensor 5 measures its own traveling speed. Thetraveling speed measured by the vehicle speed sensor 5 is delivered tothe car navigation system 1 as speed data. The GPS receiver 6 receivesGPS signals transmitted from the GPS satellites. The GPS signalsreceived by the GPS receiver 6 are delivered to the car navigationsystem 1 as GPS data. The acceleration sensor 7 measures changes in thehorizontal direction and vertical direction of its own. The changes inthe horizontal direction and vertical direction measured by theacceleration sensor 7 are delivered to the car navigation system 1 asacceleration data.

Next, the details of the car navigation system 1 will be described. Thecar navigation system 1 includes a display map calculating section 10, aroute calculating section 11, a display control section 12, a speechoutput control section 13, an input receiving section 14, a positioningsection 15, an HDD (Hard Disk Drive) 16, an HDD access section 17, atemporary memory 18, a new road detecting section 19, a new roadregistration decision section 20, a new road registration section 21 anda control section 22.

According to procedures programmed in advance, the control section 22controls data transmission and reception between the display mapcalculating section 10, route calculating section 11, display controlsection 12, speech output control section 13, input receiving section14, positioning section 15, HDD access section 17, temporary memory 18,new road detecting section 19, new road registration decision section 20and new road registration section 21, which constitute the carnavigation system 1. The data transmission and reception between thecomponents are carried out via the control section 22. For the sake ofbrevity of the explanation, the following description is made withoutreferring to the fact that the data transmission and reception iscarried out via the control section 22.

The display map calculating section 10 calculates the map image fordisplay from the map information delivered from the HDD 16 via the HDDaccess section 17 and the positioning data delivered from thepositioning section 15. The map image for display calculated by thedisplay map calculating section 10 is delivered to the display controlsection 12. The route calculating section 11 sets as the starting pointof the route the present location indicated by the positioning datadelivered from the positioning section 15 or the position delivered fromthe input receiving section 14; sets as the ending point of the routethe other position delivered from the input receiving section 14; andcalculates the optimum route (sometimes referred to as a “recommendedroute”) between the two points. The optimum route calculated by theroute calculating section 11 is delivered to the display control section12.

The display control section 12 converts the map image for displaydelivered from the display map calculating section 10 and the optimumroute delivered from the route calculating section 11 to the format thedisplay unit 2 can display, and delivers to the display unit 2 as thedisplay data. The speech output control section 13 converts the speechinformation for leading the way to the destination in accordance withthe optimum route delivered from the route calculating section 11 andthe speech information for providing the driver with the prescribedinformation contained in the map information to the format the speechoutput unit 3 can output, and delivers to the speech output unit 3 asthe speech data.

The input receiving section 14 receives the operation data deliveredfrom the input unit 4 connected to the outside. The operation datareceived by the input receiving section 14 is delivered to the displaymap calculating section 10, route calculating section 11 and the like.The positioning section 15 determines its own present location from thespeed data from the vehicle speed sensor 5, the acceleration data fromthe acceleration sensor 7 and the GPS data from the GPS receiver 6;compares the determined present location with the road informationcontained in the map information read from the HDD 16 via the HDD accesssection 17; and calculates on which road the present location is placedamong the roads indicated by the road information. The result calculatedby the positioning section 15 is delivered to the display mapcalculating section 10 and route calculating section 11 as thepositioning data. The positioning data is used by the display mapcalculating section 10 to calculate its own neighboring map, and by theroute calculating section 11 to calculate the optimum route.

The HDD 16 corresponds to a map information storage section inaccordance with the present invention. The HDD 16 records the mapinformation including the road data in advance at the shipment of thecar navigation system 1. The map information is arranged as a set ofarea map information items about individual areas reticulated bylatitude and longitude lines. Each area is referred to as “mesh”. TheHDD access section 17 controls writing and reading of the data to andfrom the HDD 16. The temporary memory 18, which is composed of avolatile memory, for example, is used for temporarily storing data.

When the display map calculating section 10, route calculating section11, speech output control section 13 and positioning section 15 eachcarry out their processing using the road information about a road(referred to as “existing road” from now on) contained in the mapinformation recorded in the HDD 16, they each read the area mapinformation corresponding to the mesh used in the processing from theHDD 16 through the HDD access section 17, store the read data in thetemporary memory 18, and carry out the processing using the stored data.

The new road detecting section 19 compares the map information read fromthe HDD 16 via the HDD access section 17 with the vehicle positioncontained in the positioning data delivered from the positioning section15; and detects the road the vehicle is traveling as a new road if thevehicle position is not on any existing roads. The coordinates of thenew road detected by the new road detecting section 19 are stored in thetemporary memory 18.

The new road registration decision section 20 reads the coordinates ofthe new road detected by the new road detecting section 19 from thetemporary memory 18; and decides whether to make additional registrationof the road represented by the coordinates to the map information thathas already been stored in the HDD 16. The decision result by the newroad registration decision section 20 is delivered to the new roadregistration section 21. The processing carried out by the new roadregistration decision section 20 will be described in detail later.

The new road registration section 21 delivers the new road informationabout the new road passing through the positive decision by the new roadregistration decision section 20 to the HDD 16 via the HDD accesssection 17 to make additional registration of the new road to the mapinformation that has already been recorded in the HDD 16.

Next, referring to the flowchart shown in FIG. 2, the operation of themap information processing apparatus of the embodiment 1 in accordancewith the present invention will be described with concentrating on theregistration decision processing carried out by the new roadregistration decision section 20. The map information processingapparatus of the embodiment 1 employs map information size as roaddensity.

When the new road registration decision section 20 starts theregistration decision processing, it identifies the map information meshcorresponding to the new road to be decided (step ST1). When the newroad extends over a plurality of meshes, all the meshes are identified.When the map information has a plurality of levels, the mesh isidentified at the level the positioning section 15 uses. When the mapinformation consists of a plurality of types of the map information, themesh is identified in the map information of the type the positioningsection 15 uses.

Subsequently, one of the meshes identified at step ST1 is selected (stepST2). Then the map information size of the selected mesh is calculated(step ST3). Subsequently, the map information size calculated at stepST3 is compared with a predetermined value (step ST4). When it has beendecided at step ST4 that the map information size is equal or less thanthe predetermined value, a new road registrable decision is made (stepST5), and the registration decision processing is completed. Thedecision result of the new road registration decision section 20 isdelivered to the new road registration section 21 as described above.

In contrast, when it has been decided at step ST4 that the mapinformation size of the mesh calculated at step ST3 is greater than thepredetermined value, the presence or absence of a mesh that has not yetpassed the information size decision is checked among the meshesidentified at step ST1 (step ST6). When it has been decided at step ST6that the uncompleted mesh is present, the sequence is returned to stepST2. On the other hand, when it has been decided that the uncompletedmesh is not present, the new road unregistrable decision is made (stepST7), and the registration decision processing is completed. Thedecision result of the new road registration decision section 20 isdelivered to the new road registration section 21 as described above.

As described above, the map information processing apparatus of theembodiment 1 in accordance with the present invention is configured insuch a manner as to employ the map information size of the mesh as theroad density, and to make a decision whether to conduct additionalregistration of the new road information to the existing map informationaccording to the map information size. Thus, the present embodiment 1can add the new road not present on the map to the existing mapinformation with eliminating or reducing the adverse effect on thenavigation functions resulting from adding the new road informationincluding the positioning error to the existing map information. Inaddition, since it employs the map information size as the road density,it can reduce the amount of calculation and calculate the road densityin a very short time.

Although the present embodiment 1 is configured in such a manner as tomake additional registration of the new road information representingthe new road into the map information already stored in the HDD 16, thisis not essential. For example, such a configuration is also possiblewhich stores the new road information on a mesh by mesh basis in the HDD16 independently of the map information, and refers to the new road mapinformation corresponding to that mesh when the HDD access section 17accesses the map information about a particular mesh. The configurationoffers the same advantage as described above.

In addition, although the present embodiment 1 is configured in such amanner as to make a new road unregistrable decision when the mapinformation size of all the meshes is greater than the predeterminedvalue when the new road extends over a plurality of meshes, this is notessential. For example, such a configuration is also possible whichmakes a new road unregistrable decision when the map information size ofat least one mesh is greater than the predetermined value. Theconfiguration offers an advantage of being able to reduce the amount ofcalculation.

Embodiment 2

The map information processing apparatus of an embodiment 2 inaccordance with the present invention decides whether to make additionalregistration of the new road to the existing map information by using asthe road density the number of links connecting a node to another node,that is, the number of roads connecting an intersection to anotherintersection.

The configuration of the map information processing apparatus of thepresent embodiment 2 is the same as that of the map informationprocessing apparatus of the embodiment 1 as shown in FIG. 1 except forthe processing executed by the new road registration decision section20.

FIG. 3 is a flowchart illustrating the registration decision processingcarried out by the new road registration decision section 20 of the mapinformation processing apparatus of the present embodiment 2. When thenew road registration decision section 20 starts the registrationdecision processing, it identifies the map information meshcorresponding to the new road to be decided (step ST1). When the newroad extends over a plurality of meshes, all the meshes are identified.When the map information has a plurality of levels, the mesh isidentified at the level the positioning section 15 uses. When the mapinformation consists of a plurality of types of the map information, themesh is identified in the map information of the type the positioningsection 15 uses.

Subsequently, one of the meshes identified at step ST1 is selected (stepST2). Then the map information about the selected mesh is obtained (stepST11). Subsequently, the number of links (the number of roads) includedin the map information obtained at step ST11 is calculated (step ST12).Then, the number of links calculated at step ST12 is compared with apredetermined value (step ST13). When it has been decided at step ST13that the number of links is equal to or less than the predeterminedvalue, a new road registrable decision is made (step ST5), and theregistration decision processing is completed. The decision result ofthe new road registration decision section 20 is delivered to the newroad registration section 21 as described above.

In contrast, when it has been decided at step ST13 that the number oflinks calculated at step ST3 is greater than the predetermined value,the presence or absence of a mesh that has not yet passed the decisionas to the number of links is checked among the meshes identified at stepST1 (step ST14). When it has been decided at step ST14 that theuncompleted mesh is present, the sequence is returned to step ST2. Onthe other hand, when it has been decided that the uncompleted mesh isnot present, the new road unregistrable decision is made (step ST7), andthe registration decision processing is completed. The decision resultof the new road registration decision section 20 is delivered to the newroad registration section 21 as described above.

As described above, the map information processing apparatus of theembodiment 2 in accordance with the present invention is configured insuch a manner as to make a decision whether to conduct additionalregistration of the new road information to the existing map informationaccording to the number of roads used as the road density, that is, thenumber of links in the map information. Thus, the present embodiment 2can add the new road not present on the map to the existing mapinformation with eliminating or reducing the adverse effect on thenavigation functions resulting from adding the new road informationincluding the positioning error to the existing map information. Inaddition, since it employs the number of links as the road density, itcan calculate the road density accurately in a short time.

Embodiment 3

The map information processing apparatus of an embodiment 3 inaccordance with the present invention decides whether to make additionalregistration of the new road to the existing map information by using asthe road density the total length of the links connecting a node toanother node, that is, the total length of the roads connecting anintersection to another intersection.

The configuration of the map information processing apparatus of thepresent embodiment 3 is the same as that of the map informationprocessing apparatus of the embodiment 1 as shown in FIG. 1 except forthe processing executed by the new road registration decision section20.

FIG. 4 is a flowchart illustrating the registration decision processingcarried out by the new road registration decision section 20 of the mapinformation processing apparatus of the present embodiment 3. When thenew road registration decision section 20 starts the registrationdecision processing, it identifies the map information meshcorresponding to the new road to be decided (step ST1). When the newroad extends over a plurality of meshes, all the meshes are identified.When the map information has a plurality of levels, the mesh isidentified at the level the positioning section 15 uses. When the mapinformation consists of a plurality of types of the map information, themesh is identified in the map information of the type the positioningsection 15 uses.

Subsequently, one of the meshes identified at step ST1 is selected (stepST2). Then the map information about the selected mesh is obtained (stepST11). Subsequently, the total distance is calculated of the links(roads) contained in the map information obtained at step ST11 (stepST21). The calculation of the total distance of the links is carried outby summing up the distances of the links with sequentially referring tothe links contained in the map information. Subsequently, the totaldistance of the links calculated at step ST21 is compared with apredetermined value (step ST22). When it has been decided at step ST22that the total distance of the links is equal to or less than thepredetermined value, a new road registrable decision is made (step ST5),and the registration decision processing is completed. The decisionresult of the new road registration decision section 20 is delivered tothe new road registration section 21 as described above.

In contrast, when it has been decided at step ST22 that the totaldistance of the links calculated at step ST3 is greater than thepredetermined value, the presence or absence of a mesh that has not yetpassed the decision as to the total distance of the links is checkedamong the meshes identified at step ST1 (step ST23). When it has beendecided at step ST23 that the uncompleted mesh is present, the sequenceis returned to step ST2. On the other hand, when it has been decidedthat the uncompleted mesh is not present, the new road unregistrabledecision is made (step ST7), and the registration decision processing iscompleted. The decision result of the new road registration decisionsection 20 is delivered to the new road registration section 21 asdescribed above.

As described above, the map information processing apparatus of theembodiment 3 in accordance with the present invention is configured insuch a manner as to make a decision whether to conduct additionalregistration of the new road information to the existing map informationaccording to the total distance of the roads, which is used as the roaddensity, that is, the total distance between the nodes in the mapinformation. Thus, the present embodiment 3 can add the new road notpresent on the map to the existing map information with eliminating orreducing the adverse effect on the navigation functions resulting fromadding the new road information including the positioning error to theexisting map information. In addition, since it employs the totaldistance between the nodes as the road density, it can calculate theroad density very accurately.

Embodiment 4

To confirm the validity of the new road, the map information processingapparatus of an embodiment 4 in accordance with the present inventioncarries out the route calculation by using the map information includingthe new road detected; and decides whether to make additionalregistration of the new road to the map information depending on whethera recommended route obtained by the route calculation includes the newroad.

FIG. 5 is a block diagram showing a configuration of the map informationprocessing apparatus of the embodiment 4 in accordance with the presentinvention. The map information processing apparatus differs from the mapinformation processing apparatus of the embodiment 1 in that a new roaddeleting section 23 is added to the car navigation system 1 of the mapinformation processing apparatus of the embodiment 1 as shown in FIG. 1,and that the new road registration decision section 20 and new roadregistration section 21 carry out different processing.

The new road registration decision section 20 decides whether to makeadditional registration of the new road detected by the new roaddetecting section 19 to the map information that has already beenrecorded in the HDD 16 according to the calculation result of the routecalculating section 11. The decision result of the new road registrationdecision section 20 is delivered to the new road registration section21. The processing carried out by the new road registration decisionsection 20 will be described in detail later.

The new road registration section 21 makes additional registration ofthe new road information representing the new road detected by the newroad detecting section 19 to the map information that has already beenrecorded in the HDD 16 by delivering the new road information to the HDD16 via the HDD access section 17. The new road deleting section 23deletes the new road information, which has been additionally registeredto the HDD 16 by the new road registration section 21, by providing aninstruction to the HDD 16 via the HDD access section 17.

Next, referring to the flowcharts shown in FIG. 6 and FIG. 7, theoperation of the map information processing apparatus of the embodiment4 in accordance with the present invention will be described withconcentrating on the registration processing carried out by the new roadregistration section 21 and on the registration decision processingcarried out by the new road registration decision section 20 when thenew road detecting section 19 detects the new road. The map informationprocessing apparatus of the embodiment 1 employs the map informationsize as the road density.

As shown in the flowchart of FIG. 6, when the new road detecting section19 detects the new road, the new road registration section 21 makesadditional registration of the new road detected to the map informationthat has already been stored in the HDD 16 (step ST101). Subsequently,the new road registration decision section 20 carries out theregistration decision processing (step ST102), which will be describedin detail later.

Subsequently, a decision is made as to whether the registration decisionprocessing at step ST102 makes a registrable decision of the new road(step ST103). When the registrable decision is made, since theregistration decision processing at step ST102 has already additionallyregistered the new road to the map information that has already beenstored in the HDD 16, the registration processing is completed. On theother hand, when an unregistrable decision is made at step ST103, sincethe registration decision processing at step ST102 has alreadyadditionally registered the new road to the map information that hasalready been stored in the HDD 16, the processing of deleting theregistered new road is carried out (step ST104). Thus, the new roaddeleting section 23 deletes the new road registered in the HDD 16 by thenew road registration section 21.

Next, the details of the registration decision processing at step ST102will be described with reference to the flowchart shown in FIG. 7. Theregistration decision processing sets a calculation starting point(search start position) used in the route calculation for confirming thevalidity of the new road (step ST31). As the calculation starting point,the position registered as user's house is set, for example.Subsequently, a calculation ending point (search end position) used inthe route calculation is set (step ST32). As the calculation endingpoint, the present location of the vehicle is set, for example. Thussetting the calculation starting point and calculation ending pointenables an appropriate decision as to whether the new road is aneffective route for the user or not.

Subsequently, the route calculating section 11 calculates a recommendedroute between the starting point set at step ST31 and the ending pointset at step ST32 (step ST33). Then, a decision is made as to whether thecalculated recommended route includes a new road or not (step ST34).When it has been decided at step ST34 that the recommended routeincludes the new road, a new road registrable decision is made (stepST5), and the registration decision processing is completed. Thedecision result of the new road registration decision section 20 isdelivered to the new road registration section 21 as described above. Onthe other hand, when it has been decided at step ST34 that therecommended route does not include the new road, a new roadunregistrable decision is made (step ST7), and the registration decisionprocessing is completed. The decision result of the new roadregistration decision section 20 is delivered to the new roadregistration section 21 as described above.

The route calculation at step ST33 utilizes a route calculatingtechnique already known in the car navigation field. To calculate therecommended route between given two points by utilizing the routecalculating technique, the starting point and the ending point areusually obtained as follows. First, the starting point of the routecalculation is determined by searching for a nearest link (road), thatis, the closest link to the given calculation starting point, and bysetting the closest point on the closest link obtained by the search asthe starting point (the closest point is the foot of the perpendicularfrom the calculation starting point to the closest link; or when nointersection point is present between the perpendicular and the closestlink line, the closest point is an end point of the closest link nearerto the calculation starting point). Likewise, the ending point of theroute calculation is determined by searching for a nearest link (road),that is, the closest link to the given calculation ending point, and bysetting the closest point on the closest link obtained by the search asthe ending point (the closest point is the foot of the perpendicularfrom the calculation ending point to the closest link; or when nointersection point is present between the perpendicular and the closestlink line, the closest point is an end point of the closest link nearerto the calculation ending point).

For example, in the conditions as shown in FIG. 8 in which a point S isgiven as the calculation starting point of the route search, links aresearched for within a radius r (500 m, for example) from the point S. Inthe example as shown in FIG. 8, five links, link L1, link L2, link L3,link L4 and link L5, are found. Next, the distance from the point S toeach link is calculated. When a perpendicular from the point S to thelink can be drawn, the distance to the link is the length of theperpendicular. In contrast, when a perpendicular from the point S to thelink cannot be drawn, the distance is defined as the distance from thepoint S to the closer end of the link.

In the example as shown in FIG. 8, a perpendicular can be drawn from thepoint S to each of the links L1, L2 and L3. Accordingly, the lengths ofthe perpendiculars, d1, d2 and d3, are the distances from the point S tothe links. As for the links L4 and L5, a perpendicular cannot be drawnfrom the point S to the links. Accordingly, the distance from the pointS to the closer ends of the links L4 and L5, that is, d4, is thedistance from the point S to these links. The distances d1, d2, d3 andd4 calculated in this way are compared with each other, and the shortestdistance d1 is obtained. Then, using the position V1 at the distance d1from the point S as the starting point, the route calculating processingis carried out. To obtain the route calculation ending point(destination), the foregoing processing is carried out.

Although the map information processing apparatus of the presentembodiment 4 is described by way of example which sets the user's houseas the starting point of the route calculation for confirming thevalidity of the new road, and which sets the present location of thevehicle as the ending point, this is not essential. For example, toconfirm the validity of the new road, it is also possible to set as thestarting point a position at a predetermined distance from the positionregistered as the user's house, and to set as the ending point aposition at a predetermined distance from the present location, offeringthe same advantage.

In addition, although the map information processing apparatus of thepresent embodiment 4 calculates the distance to each link within thepredetermined radius r from the route calculation starting point orending point, and makes the link at the shortest distance as theneighborhood link, this is not essential. For example, such aconfiguration is also possible that sets a rectangle of prescribeddimensions, which is formed by lines parallel to the longitudinaldirection and latitudinal direction with the route calculation startingpoint or ending point as the central point; calculates the distance toeach link in the rectangle; and sets the link at the shortest distanceas the neighborhood link.

Furthermore, such a configuration is also possible that calculates thedistance to each link in the mesh including the route calculationstarting point or ending point, and sets the link at the shortestdistance as the neighborhood link. Alternatively, such a configurationis also possible that calculates the distance to each link in the meshincluding the route calculation starting point or ending point or in itsneighboring meshes, and sets the link at the shortest distance as theneighborhood link.

In addition, although the map information processing apparatus of thepresent embodiment 4 sets the user's house as the starting point of theroute calculation for confirming the validity of the new road, and setsthe present location of the vehicle as the ending point, this is notessential. For example, it is possible to select any one of thepositions P1 to P7 shown in FIG. 9 as the starting point (predeterminedsearch start position). Here, P1 is the position of the user's house; P2is the starting point of a new road M1; P3 is the position apredetermined distance short of the starting point of the new road M1;P4 is the starting (ending) point of a road before the new road M1 isdetected; P5 is the starting point of a route M2 before the new road M1is detected; P6 is the position at which the car navigation system isstarted; and P7 is the position from which the traveling starts thatday.

Furthermore, it is possible to select any one of the positions Q1 to Q6shown in FIG. 9 as the ending point (predetermined search end position).Here, Q1 is the present location M3; Q2 is the ending point of the newroad M1; Q3 is the position a predetermined distance ahead of the endingpoint of the new road M1; Q4 is the starting (ending) point of the roadafter the new road M1 is detected; Q5 is the position a predetermineddistance ahead of the present location M3; and Q6 is the ending point ofthe route M2 before the new road M1 is detected. Here, such aconfiguration is also possible that selects one of the points Q1-Q6 asthe starting point, and one of the points P1-P7 as the ending point.Alternatively, a configuration is also possible that employs a pluralityof combinations of the foregoing starting points and ending points todecide the validity.

As described above, the map information processing apparatus of theembodiment 4 in accordance with the present invention can add, among thenew roads detected, only the new road convenient to the user by decidingwhether to add or not from the viewpoint of the traveling distance andtraveling time such as whether to employ or not as the recommended routein the route calculation. Accordingly, addition of needless new roadinformation can be circumvented. Besides, traveling across a parking lotof facilities having different entrance and exit can be excluded fromaddition. Suitably selecting the route calculation starting point andending point enables an appropriate decision as to whether the new roadis convenient to the user or not.

Embodiment 5

The map information processing apparatus of an embodiment 5 inaccordance with the present invention decides whether to make additionalregistration of the new road information to the existing map informationor not according to the road type of the new road detected or to thetype of a road to which the new road is joined.

The map information processing apparatus of the present embodiment 5 hasthe same configuration as the map information processing apparatus ofthe embodiment 1 shown in FIG. 1 except for the processing carried outby the new road detecting section 19 and new road registration decisionsection 20. At the new road information collection carried out atpredetermined intervals, if the vehicle position measured by thepositioning section 15 is not present on the existing roads, the newroad detecting section 19 decides that the road the vehicle is travelingis a new road, and stores its coordinates to the temporary memory 18. Inaddition, the new road detecting section 19 calculates the travelingspeed at the point of the coordinates stored in the temporary memory 18from the traveling time and traveling distance, and stores it in thetemporary memory 18 as well.

Next, referring to the flowcharts shown in FIG. 10 and FIG. 11, theoperation of the map information processing apparatus of the embodiment5 in accordance with the present invention will be described withconcentrating on the registration decision processing carried out by thenew road registration decision section 20.

When the new road registration decision section 20 starts theregistration decision processing, it first obtains the road types ofexisting roads joined to the starting point and ending point of the newroad to be decided. Then it checks whether at least one of themindicates an expressway (step ST41). When it has been decided at stepST41 that the road type of at least one of the existing roads joined tothe starting point and ending point of the new road is an expressway, anew road registrable decision is made (step ST5), and the registrationdecision processing is completed. The decision result of the new roadregistration decision section 20 is delivered to the new roadregistration section 21 as described above.

On the other hand, when it has been decided at step ST41 that the roadtype of none of the existing roads joined to the starting point andending point of the new road is an expressway, road type decisionprocessing of the new road is carried out (step ST42). The details ofthe road type decision processing will be described later. Subsequently,according to the result of the road type decision processing, a decisionis made as to whether the type of the new road is an expressway or not(step ST43). If it has been decided at step ST43 that the new road isthe expressway, a new road registrable decision is made (step ST5), andthe registration decision processing is completed. The decision resultof the new road registration decision section 20 is delivered to the newroad registration section 21 as described above. On the other hand, ifit has been decided at step ST43 that the new road is not theexpressway, a new road unregistrable decision is made (step ST7), andthe registration decision processing is completed. The decision resultof the new road registration decision section 20 is delivered to the newroad registration section 21 as described above.

Next, the details of the road type decision processing of the new roadcarried out at step ST42 will be described with reference to theflowchart shown in FIG. 11. First, the road type decision processing ofthe new road calculates the average speed of traveling the new road fromthe speed data which is obtained at the new road information collectionand stored in the temporary memory 18 (step ST201). Subsequently, adecision is made as to whether the average speed calculated is equal toor greater than a predetermined value (step ST202). When it has beendecided that the average speed is equal to or greater than thepredetermined value, the new road is decided as the expressway (stepST203), and the road type decision is completed. On the other hand, whenit has been decided at step ST202 that the average speed is less thanthe predetermined value, a decision is made that the new road is not theexpressway (step ST204), and the road type decision is completed.

Although the map information processing apparatus of the presentembodiment 5 is configured in such a manner as to make a decisionwhether the new road is the expressway or not according to the averagespeed, this is not essential. For example, a configuration is alsopossible that decides the new road as an ordinary road if it includes acurve whose turning radius is less than a predetermined value.

In addition, although the map information processing apparatus of thepresent embodiment 5 is configured in such a manner as to make adecision whether the type of the new road is an expressway, this is notessential. For example, a configuration is also possible that makes adecision whether the new road is a toll road or a road for exclusive useof automobiles.

As described above, the map information processing apparatus of theembodiment 5 in accordance with the present invention can add a new roadassociated with a road of a road type convenient to the user such as anexpressway (or toll road or road for exclusive use of automobiles). Inaddition, it can make the decision easily that the new road is anexpressway (or toll road or road for exclusive use of automobiles) in anappropriate, practical way.

Embodiment 6

The map information processing apparatus of an embodiment 6 inaccordance with the present invention is configured in such a manner asto decide whether to make additional registration of the new road to theexisting map information by utilizing the data used by an electronictoll collection system (abbreviated to “ETC” from now on).

FIG. 12 is a block diagram showing a configuration of the mapinformation processing apparatus of the embodiment 6 in accordance withthe present invention. The map information processing apparatus isconfigured by adding a vehicle-mounted ETC terminal 8 to the mapinformation processing apparatus of the embodiment 1 shown in FIG. 1 andby adding an ETC data receiving section 24 to the car navigation system1. In addition, the processing carried out by the new road detectingsection 19 and new road registration decision section 20 differs fromthat of the map information processing apparatus of the embodiment 1.

The vehicle-mounted ETC terminal 8 transmits and receives, when passingthrough a gateway of a toll road (tollgate), the electronic tollcollection data, the information about passing through the tollgate,through radio communications with an ETC roadside apparatus (not shown)installed in the gateway, thereby paying the toll. The electronic tollcollection data transmitted and received by the vehicle-mounted ETCterminal 8 is delivered to the ETC data receiving section 24 of the carnavigation system 1.

Receiving the electronic toll collection data from the vehicle-mountedETC terminal 8, the ETC data receiving section 24 stores it in thetemporary memory 18 as the toll road traveling state information. Thetoll road traveling state information stored in the temporary memory 18is changed from a “toll road traveling” state to an “ordinary roadtraveling” state in the following cases: when the ETC data receivingsection 24 receives the electronic toll collection data from thevehicle-mounted ETC terminal 8; when the positioning section 15 measuresthat the vehicle position is on an existing ordinary road; and when itis detected that the vehicle passes through a curve whose turning radiusis less than a prescribed turning radius.

The new road detecting section 19 makes a new road decision when thevehicle position measured by the positioning section 15 is not on theexisting road, and stores its coordinates to the temporary memory 18. Atthe same time, at the starting point of the new road, the new roaddetecting section 19, referring to the toll road traveling stateinformation in the temporary memory 18, decides whether the currenttraveling road is a toll road or not, and stores into the temporarymemory 18 the decision result with establishing correspondence with thecoordinates of the starting point of the new road. In addition, when theETC data receiving section 24 receives the electronic toll collectiondata from the vehicle-mounted ETC terminal 8 in the state the new roadis detected, the new road detecting section 19 stores into the temporarymemory 18 the changes in the toll road traveling state with establishingcorrespondence with the coordinates of the position.

Next, referring to the flowchart shown in FIG. 13, the operation of themap information processing apparatus of the embodiment 6 in accordancewith the present invention will be described with concentrating on theregistration decision processing carried out by the new roadregistration decision section 20.

The registration decision processing carried out by the new roadregistration decision section 20 is the same as the registrationdecision processing of the embodiment 5 described with reference to theflowchart of FIG. 10 except for the following point. More specifically,the road type decision processing of the new road carried out at stepST42 of the flowchart shown in FIG. 10 differs from that of theembodiment 5. Here, the road type decision processing of the new roadwill be described in detail with reference to the flowchart shown inFIG. 13.

First, the road type decision processing of the new road decides fromthe temporary memory 18 as to whether the toll road traveling state atthe starting point of the new road indicates the “toll road traveling”or not (step ST211). When it has been decided that it indicates the“toll road traveling”, a decision is made that the new road is anexpressway (step ST203), and the road type decision is completed. On theother hand, when it has been decided that it does not indicate the “tollroad traveling” at step ST211, a decision is made subsequently as towhether the new road includes a position at which the toll roadtraveling state is changed to the “toll road traveling” or not (stepST212). The decision is made by checking the presence or absence of thecoordinates of the point at which the toll road traveling stateinformation, which is associated with the coordinates stored in thetemporary memory 18 as the new road, is changed to “toll roadtraveling”.

When it has been decided at step ST212 that the new road includes theposition at which the toll road traveling state is changed to “toll roadtraveling”, a decision is made that the new road is an expressway (stepST203), and the road type decision is completed. On the other hand, whenit has been decided at step ST212 that the new road does not include theposition at which the toll road traveling state is changed to “toll roadtraveling”, a decision is made that the new road is not an expressway(step ST204), and the road type decision is completed.

Here, the map information processing apparatus of the embodiment 6 makesa backup of the information indicating the toll road traveling statestored in the temporary memory 18 into the HDD 16 when the power supplyof the car navigation system 1 is turned off. When the power supply ofthe car navigation system 1 is turned on again, the backup informationis read from the HDD 16 and developed on the temporary memory 18.

Although the present the map information processing apparatus of theembodiment 6 is configured in such a manner as to decide whether theroad type of the new road is a toll road or not, this is not essential.For example, it can be configured in such a manner as to decide whetherthe road type of the new road is an expressway or road for exclusive useof automobiles.

As described above, the map information processing apparatus of theembodiment 6 in accordance with the present invention is configured insuch a manner as to make the toll road (or expressway or road forexclusive use of automobiles) decision according to the electronic tollcollection data acquired from the vehicle-mounted ETC terminal 8. Thus,it can make that decision appropriately and easily.

Embodiment 7

The map information processing apparatus of an embodiment 7 inaccordance with the present invention is configured in such a manner asto decide whether to make additional registration of the new road to theexisting map information depending on whether the new road detected isat a predetermined position such as in the neighborhood of the user'shouse.

The configuration of the map information processing apparatus of thepresent embodiment 7 is the same as that of the map informationprocessing apparatus of the embodiment 1 shown in FIG. 1 except for theprocessing carried out by the new road registration decision section 20.

Next, referring to the flowchart shown in FIG. 14 the operation of themap information processing apparatus of the embodiment 7 in accordancewith the present invention will be described with concentrating on theregistration decision processing carried out by the new roadregistration decision section 20.

When the new road registration decision section 20 starts theregistration decision processing, it first carries out user's houseperiphery decision processing of a new road (step ST51). The user'shouse periphery decision processing makes a decision as to whether a newroad is present within a predetermined distance, 5 km, for example, fromthe user's house. Subsequently, according to the decision result at stepST51, a decision is made as to whether the new road is in the user'shouse periphery (step ST52). When it has been decided that the new roadis in the user's house periphery, a new road registrable decision ismade (step ST5), and the registration decision processing is completed.The decision result of the new road registration decision section 20 isdelivered to the new road registration section 21 as described above. Onthe other hand, when it has been decided at step ST52 that the new roadis not in the user's house periphery, a new road unregistrable decisionis made (step ST7), and the registration decision processing iscompleted. The decision result of the new road registration decisionsection 20 is delivered to the new road registration section 21 asdescribed above.

Although the foregoing user's house periphery decision processing isconfigured in such a manner as to decide whether the new road is withinthe predetermined distance from the user's house, this is not essential.For example, a configuration is also possible that makes a decision asto whether the new road is in the same mesh as the user's house.Alternatively, a configuration is also possible that makes a decision asto whether the new road is in the same mesh as the user's house, or inits adjacent meshes. Although the user's house periphery decisionprocessing of the map information processing apparatus of the presentembodiment 7 is configured in such a manner as to decide whether the newroad is in the user's house periphery, this is not essential. Forexample, such a configuration is also possible that makes a decision asto whether the new road is in a periphery of a predetermined positionsuch as a surrounding area of facilities into which the user oftenwalks. Alternatively, a configuration is also possible that makes adecision as to whether the new road is in the periphery of the positionthe user registers or not.

As described above, the map information processing apparatus of theembodiment 7 in accordance with the present invention is configured insuch a manner as to make additional registration of the new road to theexisting map information when the new road detected is in the user'shouse periphery. Accordingly, the new road in the area convenient to theuser can be added. In addition, the area convenient to the user can bedecided appropriately and easily.

Embodiment 8

The map information processing apparatus of an embodiment 8 inaccordance with the present invention is configured in such a mannerthat it presents to the user the result of a decision as to whether tomake additional registration of the new road information representingthe new road detected to the existing map information; and that when theuser gives confirmation of its registration in response to thepresentation, the new road information is additionally registered to theexisting map information.

FIG. 15 is a block diagram showing a configuration of the mapinformation processing apparatus of the embodiment 8 in accordance withthe present invention. The map information processing apparatus isconfigured by adding a registration decision result presentation section25 and a registration decision result confirmation section 26 to the carnavigation system 1 of the map information processing apparatus of theembodiment 1 shown in FIG. 1. In addition, it differs from the mapinformation processing apparatus of the embodiment 1 in the processingcarried out by the new road registration section 21. More specifically,the new road registration section 21 carries out the registrationprocessing of the new road when the registration decision resultconfirmation section 26 gives the confirmation of registering the newroad.

Next, referring to the flowchart shown in FIG. 16, the operation of themap information processing apparatus of the embodiment 8 in accordancewith the present invention will be described with concentrating on theprocessing carried out by the registration decision result presentationsection 25 and registration decision result confirmation section 26.

In the processing, the registration decision result presentation section25 presents to the user the registration decision result made by the newroad registration decision section 20, first (step ST301). Subsequently,the registration decision result confirmation section 26 displays aninquiry about the user's intention regarding the registration decisionresult presented at step ST301 (step ST302). FIG. 17 shows an example ofa picture displayed on the display unit (monitor) 2 of the carnavigation system 1 after executing steps ST301 and ST302.

Next, a decision is made as to whether the user inputs a response (“yes”or “no”) from the input unit 4 or not (step ST303). When it has beendecided that the user has not yet input, a user input is waited for apredetermined time period (0.2 second, for example) (step ST304). Afterthat, the sequence is returned to step ST303. On the other hand, when ithas been decided at step ST303 that the user input is carried out, adecision is made as to whether the input is “yes” or not (step ST305).When it has been decided that the user input is “yes”, the processing iscompleted. On the other hand, when it has been decided that the userinput is “no”, the decision result of the new road registration decisionsection 20 is reversed (step ST306), and the processing is completed.

As described above, the map information processing apparatus of theembodiment 8 in accordance with the present invention enables the userto recognize the registration decision result of the new road. Inparticular, the present embodiment 8 offers an advantage that the usercan recognize that the new road is not unconditionally added to the mapinformation even if the user travels the new road, and can recognize itscause. In addition, even when the registration decision result thesystem automatically calculates differs from the intention of the userabout the necessity of registering the new road, the intention of usercan be reflected.

INDUSTRIAL APPLICABILITY

As described above, the map information processing apparatus inaccordance with the present invention is suitable for eliminating theadverse effect on the existing functions by making an appropriatedecision whether to make additional registration of the new road to theexisting map information or not before carrying out the registration.

What is claimed is:
 1. A map information processing apparatuscomprising: a map information storage section for storing mapinformation on an area by area basis formed in meshes; a positioningsection for measuring its own present location; a new road detectingsection for deciding that a new road is detected when the presentlocation measured by said positioning section is on a road not includedin the map information stored in said map information storage section; anew road registration decision section for deciding that the new road isadditionally registrable to the map information stored in said mapinformation storage section when road density in an area including thenew road detected by said new road detecting section is equal to or lessthan a predetermined value; and a new road registration section formaking additional registration of the new road, as to which said newroad registration decision section makes an additionally registrabledecision, to the map information stored in said map information storagesection.
 2. The map information processing apparatus according to claim1, wherein said new road registration decision section employs, as theroad density in the area including the new road, map information sizerepresenting a map information volume of the area.
 3. The mapinformation processing apparatus according to claim 1, wherein said newroad registration decision section employs, as the road density in thearea including the new road, a number of roads contained in the mapinformation about the area.
 4. The map information processing apparatusaccording to claim 1, wherein said new road registration decisionsection employs, as the road density in the area including the new road,a total distance of roads contained in the map information about thearea.
 5. The map information processing apparatus according to claim 1,further comprising a registration decision result presentation sectionfor making a presentation of a decision result and decision reason madeby said new road registration decision section.
 6. The map informationprocessing apparatus according to claim 5, further comprising: an inputreceiving section for receiving an input from an input unit; and aregistration decision result confirmation section for confirming thedecision result and decision reason presented by said registrationdecision result presentation section according to a content received bysaid input receiving section, wherein said new road registration sectiondecides that the new road is additionally registrable to the mapinformation stored in said map information storage section when saidregistration decision result confirmation section confirms that the newroad should be registered.